1. Field of the Invention
The present invention relates to ink pens, and more particularly relates to retractable ink pens, wherein an inner ink cartridge retracts within the outer body portion of the ink pen upon rotation of the outer body with respect to the top portion of the pen to which the ink cartridge is connected. Even more particularly, the present application relates to a retractable ink pen wherein an exposed clip guard prevents entry of the ink pen into a shirt pocket or the like with the ink pen's writing tip portion is exposed for operation. It should be understood that the term "ink pen" as used herein includes that type of pen commonly known as a "ball point" pen.
2. General Background and Prior Art
Several ink pens are in use today which utilize a retractable ink supply. Such an ink supply can be withdrawn into the inner portion of the ink pen when use of the pen is not desired. Thus, the ink supply and its dispensing tip are hidden from use and the inadvertent dispersing of ink is prevented. This is especially important when the user of the ink pen carries it in a pocket or similar article of clothing, since ink can be dispensed inadvertently into the clothing causing stains and the like.
Several ink pens have been patented which have attempted to solve the problem of the inadvertent dispensing of ink from the pen when not in use.
The following table provides a listing of some prior art devices which have been patented which have attempted to solve the problem of inadvertent ink loss and dispensing as aforementioned.
______________________________________ Prior Art Patents U.S. Pat. No. Inventor(s) Issue Date ______________________________________ 1,566,871 G.R. Hudson December 22, 1925 2,427,069 R.W. Randolph September 9, 1947 2,881,736 N. Zepelovitch April 14, 1959 3,033,167 K.W. Spillman May 8, 1962 3,146,758 N.A. Zepell September 1, 1964 3,181,507 R.P. Dannebaum May 4, 1965 3,344,484 N.A. Zeppel, et al October 3, 1967 3,797,945 N.A. Zeppel March 19, 1974 ______________________________________
One downfall of the devices of the prior art is that the individual can in most cases inadvertently slip or place the ink pen into the shirt pocket or like article of clothing even when the ink pen is in the operative or exposed position when the ink can readily be dispensed onto an item which it touches.
Thus, the individual must be vigilant in order to assure that the ink supply is retracted before placing it into the pocket.
Many prior art retractable ink pens have complex mechanical parts which can become broken or inoperative, thus rendering the ink pen useless.
3. General Discussion of the Present Invention
The present invention provides a retractable ink pen which has means thereon for preventing the inadvertent placement of the ink pen into a shirt pocket or like article of clothing while the ink pen is in its operative or ink dispensing position. The present invention also provides a simple mechanical operating ink pen which easily and positively retracts the ink supply to the inner portion of the ink pen when not in use. The device uses only one moving part, thus minimizing the problem of breakage, or non-operability seen so often in complex mechanical ink pens of the prior art. Likewise, the simple construction of the ink pen of the present invention makes it inexpensive to manufacture.
The inner ink cartridge and outer sleeve are substantially closely associated, so that no wobble is seen. The larger diameter of the ink reservoir prevents clogging common to many small diameter ink pens. The device can be provided with a shorter overall distance between clip guard and writing end of the pen to prevent the pen from "bottoming out" in a shirt pocket with a resultant inking or puncture of the pocket itself. A greater clearance between the ink pen's point and the end portion and greater retraction of the point within the ink pen's body prevent inking of the pocket due to the accumulation of inking matter and inky matter transfusing to the bottom of the pen as with other pens. Likewise, the problem of inking on loose threads or lint in the bottom of the pocket is prevented.
There can further be provided an eraser on top of the ink pen if desired, although of course an eraser generally is not possible with pens with operating mechanisms on top.